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UMC Working - Not Working - Working again

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Here is the data:

Charged fine on the GE charger at work. Came home:


  1. Plug into 230 V/40A plug. Car has been dialed down to 30 amp since delivery. Ring turns green, Charger blinks running green. Screen in car shows 230V/30A with 0A charging.
  2. Screen on car's screen cycles through 0-230V up and down and Ring turns Red.
  3. LED on charger blinks GREEN and unit clicks 4 times with each Green but does not go Red.
  4. Unplugged charger and retried, cycled breakers and retried, pressed reset on charger and retired.

Called Tesla and they did a remote troubleshoot and think the UMC is bad.

The next morning:

  1. Tried 230V plug with same results but now charger blinks 2 times RED. Cycled power, unplug replug, hit reset. Same results.
  2. Tried on 120V/20 Amp plug. Car has been dialed down to 11A so breaker will not trip since delivery. Same results as above.
  3. Press reset on charger and car begins to charge at 11A.
  4. Removed plug from car.
  5. Plugged charger into 230V and plugged into car – car charges at 30 Amp.
  6. Unplugged at car and replug – car charges at 30 Amp again.

I will try the GE Charger at work later today and bring my UMC and try it in the plug I had put in by the GE Charger.
 
I cross my fingers every time I plug in. See this post (and the entire thread) for details. It got to the point where the UMC button wouldn't even open the charge port door. Since software 4.5 it's been much better, but the other day at the Yorkdale store, their HPWC button would not open my port and I had to use the touchscreen.
 
Both the UMC and the GE charger worked at my office. I called Tesla and their troubleshooting reported a bad charger in the car. There are two chargers, a master and a slave, the master was reporting an error and they believe the slave now is taking over and that is why I can charge on the chargers I am using. If I was using a 100 amp charger I would only be able to charge at 1/2 the amps since one charger is faulting out. they are sending someone to my house to replace the charger in the car.
 
Both the UMC and the GE charger worked at my office. I called Tesla and their troubleshooting reported a bad charger in the car. There are two chargers, a master and a slave, the master was reporting an error and they believe the slave now is taking over and that is why I can charge on the chargers I am using. If I was using a 100 amp charger I would only be able to charge at 1/2 the amps since one charger is faulting out. they are sending someone to my house to replace the charger in the car.

My car is currently in the shop having the master charger replaced (I didn't get the optional second charger, which would be the slave...). I went to go to work yesterday and found that the car did not charge overnight on Wed, which was day 8 with the car. I had enough range to get it in to service, and they diagnosed the issue shortly thereafter, but didn't get the work done yesterday. I should get it back this afternoon...